Manufacture of water and fat proof paper with glazed surface.



Warren dramas vPATENT OFFICE.

HENRIETTE IIERFS, OF BONN, GERMANY.

MANUFACTURE OF WATER AND FAT PROOF PAPER WlTH GLAZED SURFACE.

SPEGIFIGATION forming part of Letters Patent No. 697,207, dated April 8, 1902.

Application filed July 31,1901. Serial No. 70,409- (No specimens.)

To to whom, it may concern:

Be it known that I, HENRIETTE HERFS, of

Bonn, Rhenish Prussia, in the Empire of Germany, have invented certain new and useful Improvements in the Manufacture of WVater and Fat Proof Paper with Glazed Surface; and I desire hereon to secure Letters Patent.

No waterproof papers up to date hold out water for any length of. time, nor is any one of them totally uninfluenced by greasy matters. The combination of water and fat proof qualities with permanent not-removable glazure does not exist.

In this specification I call all existing preparations of paper or board the primary process to distinguish it from my process of adding, first, a solution of shellac in methylated spirits (or any other lac varnish) and then an application of talc, which I call the supplementary process, because this process is to be used supplementarily or in addition to all other processes for making paper waterproof. The employment of any lac varnish with talc alone is not possible, because the paper thereby becomes unduly brittle and easily cracks and tears.

As an example of the employment of my process may serve the following: Bleached linseed'oil is boiled and then pareffin melted in the hot oil. Best mixing proportions are one part, by weight, of paraflin to sixty-five parts, by weight, oil, (other proportions admissible.) The paper is spread with this mass and well pressed between rollers. Freed from all superfluous moisture, it is next placed between sheets of felt, exposed to heat, and finally dried, sufficient moisture being, however, left to prevent the paper becoming brittle. This process is done twice. The paper is now coated differently, my supplements being employed. Four parts, by weight, shellac are dissolved in seventeen of spirits (other suitable proportions are admissible) and mixed with one part, by weight, paraflin to thirty-three of linseed-oil. Spirits of ninety per cent. are the best. Any other varnish may be used. As before, the paper is passed between rollers and dried till it ceases to sweat. Lastly, talc (or its substitute) is finely strewn over and rubbed in by rollers or other suitable means, placed between sheets of felt, and exposed to heat. The tale application may be repeated several times. The varnish layer serves to make fatproof, enhances the waterproof qualities, and covers the smell due to oil or other matter. The tale gives glance, toughens, and thickens, yet maintains pli ancy,ductility,and prevents an easy tearinge 6., makes the paper leathery and useful, as for drinking-glass, the covers of books and documents, leaves of childrens books, and so on.

Having now particularly described and ascertained the nature of my invention and how it is to be used, what I declare as new, and desire to secure by Letters Patent thereon, is--- To employ supplementarily to (before, during, or after) all other processes for making paper waterproof, a coating of lac varnish and then a coating of talc, drying and otherwise treating the paper both after the lac and after talc coating, substantially as set forth and described.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

HENRIETTE IIERFS.

Witnesses:

CHARLES LnsIMrLn, CARL ScHMI'r'r. 

